相关论文: The White Dwarf Luminosity Function from SDSS Imag…
We present the preliminary results of a survey aimed at significantly increasing the range and completeness of the local census of spectroscopically confirmed white dwarfs. The current census of nearby white dwarfs is reasonably complete…
We present a measurement of the quasar luminosity function in the range 0.68<z<4 down to extinction corrected magnitude g_dered=22.5, using a simple and well understood target selection technique based on the time-variability of quasars.…
A reduced proper motion diagram utilizing Sloan Digital Sky Survey (SDSS) photometry and astrometry and USNO-B plate astrometry is used to separate cool white dwarf candidates from metal-weak, high-velocity main sequence Population II stars…
We present an improved spectroscopic and photometric analysis of hydrogen-line DA white dwarfs from the Sloan Digital Sky Survey Data Release 4 based on model atmospheres that include improved Stark broadening profiles with non-ideal gas…
Using galaxy sample observed by the BATC large-field multi-color sky survey and galaxy data of SDSS in the overlapped fields, we study the dependence of the restframe $r$-band galaxy luminosity function on redshift and on large-scale…
We present the full spectroscopic white dwarf and hot subdwarf sample from the SDSS first data release, DR1. We find 2551 white dwarf stars of various types, 240 hot subdwarf stars, and an additional 144 objects we have identified as…
The inversion of the white dwarf luminosity function provides an independent way to prove the past star formation history of the Milky Way independent of any cosmological models. In Rowell & Hambly (2011), the effective volume method uses…
Although it a very narrow angle survey, the depth of the HDF results in its sampling a significant volume of the halo of our galaxy. Thus it is useful for the purposes of detecting (or placing upper limits on the distribution of)…
We present a coherent and detailed Monte Carlo simulation of the population of hot white dwarfs. We assess the statistical significance of the hot end of the white dwarf luminosity function and the role played by the bolometric corrections…
A recent cross-correlation between the SDSS DR7 White Dwarf Catalog with the Wide-Field Infrared Survey Explorer ($WISE$) all-sky photometry at 3.4, 4.6, 12, and 22 microns performed by Debes et al. (2011) resulted in the discovery of 52…
The amount of mass contained in low-mass objects is investigated anew. Instead of using a mass-luminosity relation to convert a luminosity function to a mass function, I predict the mass-luminosity relation from assumed mass functions and…
White dwarfs are the fossils left by the evolution of low-and intermediate-mass stars, and have very long evolutionary timescales. This allows us to use them to explore the properties of old populations, like the Galactic halo. We present a…
We have extended our detailed survey of the local white dwarf population from 20 pc to 25 pc, effectively doubling the sample volume, which now includes 232 stars. In the process new stars within 20 pc have been added, a more uniform set of…
The evolution of white dwarfs is a simple gravothermal process. This means that their luminosity function, i.e. the number of white dwarfs per unit bolometric magnitude and unit volume as a function of bolometric magnitude, is a…
We present a detailed Monte Carlo simulation of the population of the hot branch of the white dwarf luminosity function. We used the most up-to-date stellar evolutionary models and we implemented a full description of the observational…
In Gentile Fusillo et al. (2015) we developed a selection method for white dwarf candidates which makes use of photometry, colours and proper motions to calculate a probability of being a white dwarf (Pwd). The application of our method to…
In this study, colour-magnitude relations (CMRs) for DA-type white dwarfs in the Sloan Digital Sky Survey (SDSS) photometric system were investigated. For this purpose, the SDSS data for 20,247 white dwarf stars, as provided in the study by…
Luminosity functions and their integrated luminosity densities are presented for the 6dF Galaxy Survey (6dFGS). This ongoing survey ultimately aims to measure around 150,000 redshifts and 15,000 peculiar velocities over almost the entire…
I present an algorithm for inverting the luminosity function for white dwarfs to obtain a maximum likelihood estimate of the star formation rate of the host stellar population. The algorithm is of the general class of Expectation…
The total number and luminosity function of the population of dwarf galaxies of the Milky Way (MW) provide important constraints on the nature of the dark matter and on the astrophysics of galaxy formation at low masses. However, only a…